SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Loss Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	28,050	27,837	27,284
Shares issuable in connection with acquisitions
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	0	45	157
Shares issuable upon exercise of stock options
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	1,518	2,284	2,231
Shares issuable upon the release of restricted stock awards
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	5,255	4,321	3,968
Shares issuable upon the release of performance share units
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	968	878	619
Shares issuable upon conversion of convertible notes
Common shares not included in the computation of diluted net loss per share
Antidilutive shares (in shares)	20,309	20,309	20,309